[Impulse activity of visual cortex neurons at successive stages of instrumental behavior]

Dynamics of spike activity of 62 units was studied in the projection visual area of the cerebral cortex in unrestrained cats during their performance of a conditioned alimentary instrumental reaction. Analysis of the activity of each unit was made at intervals from the beginning of the conditioned signal (light or sound) to the beginning of lapping milk which appeared in the feeding trough after the cat pressed the pedal. It has been found that the form of activity of the cortical unit greatly depends on the modality of the conditioned stimulus (light or sound). As to the final stages of instrumental behaviour and the achievment of the positive result, the degree of participation of cortical visual units in their formation does not depend on the modality of the conditioned signal.